Golang Weekly

Hooking into the Go toolchain

Fri, 9 Oct 2026 00:00:00 +0000

#620 — October 9, 2026

ℹ️ We're back, but we're taking another break next week, so we'll see you again on Friday, October 23! :-)
__
Your editor, Peter Cooper

Go Weekly

The Data Race That Wasn't a Bug (and the One That Was) — Client.Do can return before net/http has finished reading your request body, so reusing the buffer can trigger a data race. A walk through the transport’s goroutines and why VictoriaMetrics kept one such race but fixed another.

Jesús Espino

Nail Your Complex Go Backend — Adding a feature shouldn't break three other things. Learn advanced backend patterns by building a food delivery platform, by hand or with your coding agent. Enrollment opens in two weeks. Join the waitlist so you don’t miss it!

Three Dots Labs sponsor

Hooking into the Go Toolchain — A deep tour of go build -toolexec for wrapping compiler and linker runs, starting with a simple timer and moving on to rewriting code mid-build, patching importcfg to add new imports, and more.

Kemal Akkoyun

IN BRIEF:

🔐 Go 1.27.2 and 1.26.9 have been released with 15 security fixes, mostly in net/http, plus a fix for a compiler bug that could corrupt values.
📊 Every Go release since 2013, benchmarked. The same benchmark programs took 11.5% less time on Go 1.27 than on 1.23, and ~41% less than on 1.2.
🔒 Google has paused bounties for product vulnerabilities in Go and its other open source projects after a flood of mostly invalid automated reports.
🇯🇵 GopherCon Japan 2027's CFP is open until October 25 if you fancy speaking at the (bilingual) event in Tokyo next February.

Hacking the Go Compiler to Efficiently Map IPv4 to IPv6 — A small IPv4-to-IPv6 conversion led Vincent through noder hacks, SSA rewrite rules, and compiler pass ordering to close a ~8x performance gap.

Vincent Bernat

Arch-Specific SIMD in Go — A follow-up to the Go team’s look at platform-independent SIMD in Go covering the experimental archsimd package, which now supports arm64 and wasm, plus tips for writing SIMD code that compiles well.

Junyang Shao and David Chase (Go Team)

Don't Couple Your Go Code to GitHub — Is putting github.com in import paths a problem? Iain thinks so, and makes the case for using your own domain instead, but it kicked off a lively debate on Hacker News.

Iain Cambridge

Ship Go Features, Not Data Pipelines — TimescaleDB extends Postgres so your Go service gets fast analytics without a second system. Get $1000 credit.

Tiger Data (creators of TimescaleDB) sponsor

📄 Poisoning a Go Build Cache – A hands-on look at how $GOCACHE works and why sharing it in CI can be risky. Lukas Schwab

📄 Go 1.27 Detects Goroutine Leaks: I Tested It on Mine – With three caught, but one notable miss. Jules Robineau

📄 Logs in Parallel Go Tests and Where to Find Them – Hint: Go 1.25’s t.Output() is your friend. Artur Dryomov

🛠 Code & Tools

Francis: Durable Actors, Jobs and Workflows for Go — Durable actors, cron jobs, background jobs with retries, rate limiting and saga-style workflows, embedded in your app and backed by SQLite or Postgres, with an optional standalone runtime for larger clusters.

Alessandro Segala

connect-go v2 Arrives with Simpler, gRPC-Go-Style Handlers — Buf's Go RPC library drops its generic request and response wrappers, splits HTTP out from the core, and no longer sends plain Go error messages to clients. There's a migration tool, and v1/v2 can coexist in one module.

Buf

fx 40: Interactive Terminal JSON Viewer and Processor — We've linked fx a few times over the years, but v40 is a huge release: write queries inside the viewer and watch results update as you type, plus XML, HTML, EDN and MAML input, and vim-style commands.

Anton Medvedev

gopls 0.24 Prerelease – Now with LSP 3.18 support, better Go assembly handling, and a new analyzer for inconsistent E/*E error use.
Echo 5.4 – The web framework fixes several security issues (some fixes change behavior). 4.16 gets them too.
🤖 GitHub MCP Server 2.0 – GitHub's official, Go-powered MCP server adds structured outputs for agents.
Rill 0.9 – Composable, channel-based concurrency toolkit, now with first-class context support. v1.0 is not far away.
gomponents 1.4 – Build HTML views as plain Go functions. Now with faster rendering and an official agent skill.

📰 Classifieds

POKE (Publish Once, Kickoff Everywhere) is a free agent skill that audits your Go code and helps you add events, SSE and Standard Webhooks.

🐘 Many Go backends end up talking to Postgres, so you may also like our other newsletter: Postgres Weekly.

📢 Elsewhere in the ecosystem

✨ GoNIX is a UNIX-like OS that boots a Linux kernel and hands off to a Go init, with coreutils, networking, and an SSH server, all written in Go too. After some teething problems, which I reported to its creator, the instructions to boot it on Apple silicon now work well (as above). A neat experiment!
From the same author, James Mills, also comes Parley, a "federated, decentralised chat that speaks plain IRC".
Neki, PlanetScale's new sharded Postgres offering, sits behind a Go-powered proxy, and this look at its design shows how it avoids decoding Postgres wire data it doesn't need to touch.
Mitchell Hashimoto has proposed OSC 7501, a terminal protocol that lets programs report their status to the terminal. Bubble Tea 2.1 (released this week) already supports it.
🕹️ Fancy some late '90s real-time strategy? Nanolathe reimplements Total Annihilation's engine in Go, and you can play a demo in your browser.

Go 1.27's portable SIMD

Fri, 25 Sep 2026 00:00:00 +0000

#619 — September 25, 2026

Read the Web Version

👋 We're taking a break next week, so we'll be back on Friday, October 9.
__
Your editor, Peter Cooper

Go Weekly

Platform-Independent SIMD in Go — SIMD lets a CPU perform an operation on a vector of values at once. Go 1.27 brings experimental SIMD support to arm64 and wasm, plus a portable simd package that emulates SIMD where unavailable, so you don't need to write a plain Go fallback.

David Chase and Junyang Shao (Go Team)

RELATED:

hash/adler32's SIMD implementation is a good, brief example of using SIMD to get over double the speed on larger inputs.
Ben Boyter explains how he borrowed fzf's SIMD byte-matching routine to help cut his code search tool's user CPU time by nearly 4x.
Sylvain Kerkour shows off 7.5x faster ChaCha20 encryption built on Go's SIMD.

Ingest and Analytics in One Postgres. No Pipeline — Go compiles to one binary. Your data layer can be just as lean. TimescaleDB extends the Postgres you already run so ingest and analytics live in one database, not a warehouse and a pipeline. Same SQL, one system to run. Get $1000 credit to start.

Tiger Data (creators of TimescaleDB) sponsor

📢 Proposals and Updates

How Do You Add a New Keyword to Go? (For Sum Types) — Damien's design for sum types is being actively worked through. The latest sticking point is figuring out how to add a union keyword without breaking existing code or gofmt, with some useful input from Dart's Bob Nystrom.

Damien Neil et al.

Is Go's FIPS 140 Code Bloating Your Binaries? — Using crypto/rand pulls in extra crypto code even with FIPS off, so WireGuard's creator wants a build-time opt-in. Filippo Valsorda has trimmed some dependencies but argues separate builds would increase testing and maintenance work.

Jason A. Donenfeld et al.

AND MORE:

Tests are getting automatic goroutine labels so profiles and tracebacks show which test, benchmark or fuzz run was responsible.
string(x) on arbitrary integers will be restricted to byte, rune, and untyped rune constants in Go 1.28, with the proposal being accepted yesterday.
Brad Fitzpatrick is prototyping Mutex.LockChan() so a select can wait on a lock and a channel at once. Just a demo for now.
Rhys Hiltner has a stack of CLs to speed up the GC's stop-the-world phase transitions.

🛠 Code & Tools

AX: Google's Open Agentic Orchestration Runtime — Designed for large-scale throughput, AX runs AI agents akin to how Kubernetes runs pods. Declare tasks, workspaces, and models in YAML and AX sandboxes the agents and wires it all up. GitHub repo.

Jaana Dogan et al.

CodeAF: The Open-Source Software Factory for Open Models — Instead of juggling a terminal for every agent, get one window for every project. Many models, one session: the right one for each call.

AgentField.ai sponsor

🔎 Hister: A Go-Powered Search Engine for Your Own Stuff — The creator of SearX (and Colly) is back with a self-hosted personal search engine for re-finding your files or pages you’ve visited. GitHub repo.

Adam Tauber

RobotGo 1.1: Native Cross-Platform GUI Automation — Provides an API to control the mouse and keyboard, read the screen, grab screenshots, etc. on macOS, Windows, and Linux.

V Caesar et al.

NATS Server 2.15 – High-performance messaging system. There's an upgrade guide for existing users. JetStream stream moves and scaling are now safer to cancel mid-flight, and streams default to a limit of 1,000 consumers.
Terratest 2.0 – Write automated tests for your infrastructure code (think Terraform, Kubernetes, Docker, etc). Now split into 16 modules so you only pull in the SDKs you need. (Homepage.)
garble 0.18 – A tool to obfuscate Go builds so binaries have "as little information about the original source code as possible". Now requires Go 1.27, with 10-15% faster builds.
compress 1.20 – Optimized (de)compression packages, now with support for LZW and Microsoft Xpress.
🤖 Crush 0.96 – Charm's agentic coding harness now has themes!

⭐ And finally…

The First Official TinyGo Hardware 'Starter Kit' — If you want to do some hardware hacking with TinyGo, this official kit includes a RISC-V board and a variety of modules, along with tutorials for building stuff with it. If you’ve already got some boards or want to source your own, TinyGo also has a list of recommended and supported boards you can use.

TinyGo Team and Seeed Studio

A native IDE written in Go goes open source

Fri, 18 Sep 2026 00:00:00 +0000

#618 — September 18, 2026

Read the Web Version

Go Weekly

Size-Specialized Memory Allocation in Go 1.27 — Small allocations (under 80 bytes) are now up to 30% faster, and you can get the benefits just by rebuilding. Learn where the speedup comes from and why 80 bytes was the "sweet spot". Allocation-heavy programs could see a ~1% gain overall.

Michael Matloob (The Go Blog)

Stay Sharp in the Age of AI — Master.dev instructors build at Anthropic, OpenAI, Netflix, Google, and Stripe. Learn from them with hundreds of courses, live workshops, and expanded AI learning paths. New members get $100 off a yearly membership.

Master.dev sponsor

Data Races and the Limits of ThreadSanitizer in C and Go — A tour of how ThreadSanitizer (the engine behind race detection in Go) works, and the easily reachable limits where it stops catching real races. Two objects in unrelated sync.Pools colliding in Go's 128-slot table is enough to hide a race.

Phil Eaton

IN BRIEF:

The proposal for cgo without a C toolchain from last week's issue is progressing, with a CL adding a GOEXPERIMENT to trial it ahead of any approval.
The first bare-bones draft Go 1.28 release notes are available to skim, ahead of the expected February 2027 release.
🔒 The Rust team has put out an alert to maintainers of popular libraries saying there's an 'ongoing campaign' targeting them in order to compromise their systems. Go is not immune to this, so stay alert.
🇪🇺 GopherCon Europe 2027 has been announced for Berlin next June 14–17.
🇮🇹 GoLab 2026 takes place in Bologna, Italy on November 1–3.

A 40ms Go GC Pause Caused by Swap — “I’m writing this so you don’t slap your forehead like I almost did when I decided to run swap in production to absorb memory spikes.”

Fernando Simões

Scaling Go in CI by Replacing actions/setup-go — How GitHub's official actions/setup-go lets parallel jobs interfere with each other's caches, and why its cache goes stale until you touch go.mod. CloudX's alternative gives each CI job its own isolated cache.

Schwab and Downs (CloudX)

CodeAF: A New Open-Source Software Factory, Written in Go — You direct the work from one window for every project. It splits, runs, tests and merges, and asks only when it must.

AgentField.ai sponsor

📄 A Million Go Map Entries Take 38MB, Not 16MB – A look at where the extra bytes go in Go’s Swiss table map implementation and why map[T]struct{} no longer saves memory over map[T]bool. Nazar Boyko

▶️ Numbers: The Long History Behind Go's Untyped Constants – A history-heavy talk on how 1960s word sizes gave C its integer literal mess, and why you’ll never see 0x80ULL in Go code. Dave Cheney

▶️ Building a Web App with Go and HTMX Haseeb Majid

🛠 Code & Tools

Rune: A Fast, Native, Open Source IDE Built in Go — A GPU-accelerated IDE (shown off here) that’s now GPLv3 licensed. This post has interesting details on how they got their integrated terminal almost as fast as Alacritty and Ghostty without using cgo for the hot path. GitHub repo.

Ernest Romero Climent

💡 Rune is also an interesting case study for using (a fork of) Ebitengine for its GPU-powered rendering.

golang-set 3.0: A Simple, Well-Tested, Generic Set Type — While a future Go release might be adding a generic set type, this is a mature option for now. v3.0 improves performance, adds Filter and AppendFrom methods, and removes Mongo BSON support.

Ralph Caraveo

wasm2go: Translate WebAssembly Binaries into Go Code — A compiler to translate WASM binaries into a standalone Go package, so you can ship, say, a C library built with the WASI SDK inside a Go app without the added weight of a WASM engine.

Masaaki Goshima

💡 If 'wasm2go' sounds familiar, there's also ncruces/wasm2go which powers the cgo-free go-sqlite3. The key difference is ncruces/wasm2go emits pure Go, while goccy's also generates amd64 and arm64 assembly.

GoHT: Haml, Slim and EGO Template Engine for Go — Write templates alongside normal Go code. Use @haml, @slim, or @ego blocks in a .goht file, then run the generator to produce HTML-rendering Go functions.

Michael Stack

📰 Classifieds

Software Engineer - Join our "kick ass" team! Our software team operates from 17 countries and we're looking for more exceptional engineers to join our team.

🐘 Since many Go backends end up talking to Postgres, you may also like our sibling newsletter: Postgres Weekly.

str2duration 2.2 – Get a time.Duration from a string like 1h or 1w2d3s.
html2text 1.5 – Convert HTML to plain text with no dependencies.
Goldmark 2.1 – Popular Markdown parser and rendering library.
✉️ enmime 2.5 – MIME mail encoding and decoding package.
gRPC-Go 1.84.0 – High perf gRPC framework.
go-diff 0.9 – diff parser and printing library.

Building cgo code without a C compiler?

Fri, 11 Sep 2026 00:00:00 +0000

#617 — September 11, 2026

Read the Web Version

Go Weekly

Could Go Build cgo Packages Without a C Compiler? — Cross-compiling with import "C" can be painful as it needs a C toolchain. This proposal would let packages that only call pre-built C libraries describe the interface in annotated Go files, so anyone building the package wouldn't need a C compiler.

Matloob, Mui, et al. (Go Team)

💡 Another approach is to skip cgo entirely, which the SIMD and Ebitengine items later in this issue do in two quite different ways…

Become a Confident Go Backend Engineer — Build a production-grade Go backend and learn by coding. Practice the skills you need to guide your AI coding agents. Hands-on online training from the authors of Watermill. Opens in the coming weeks. Join the waitlist.

Three Dots Labs sponsor

How Debian Code Search Got Fast TurboPFor in Pure Go with SIMD — One for performance fans! A detailed write-up of using Go’s experimental simd/archsimd package to replace a C library with native Go that runs faster. Covers PGO surprises, generics for compile-time specialization, AVX2/AVX512 kernels, and more.

Michael Stapelberg

IN BRIEF:

🎉 JetBrains recently held a Go 1.27 'release party' featuring some of the Go team. ▶️ Watch the recording here, including Robert Griesemer who explains why generic methods took so long to arrive.
Long-time contributor thepudds (a.k.a. PJ) has joined the core Go team. Russ Cox is a fan, saying "What a great hire for the Go team."
Go 1.28 seems likely to reject string(x) for integers other than byte or rune, in line with go vet's warnings. (Rob Pike proposed this 14 years ago!)
Jake Bailey has some CLs in review to make encoding/json/v2 marshal slices ~4% faster than v1, after Daniel Lemire found it 1.5x slower recently.

🕹️ Ebitengine 2.10: Now Pure Go on Desktop Platforms — After years of effort, the popular 2D game engine no longer needs cgo on macOS, Linux or BSD (joining Windows in this regard) so cross-compilation is a lot easier. There’s also a new ability to run apps as a controllable guest process, either headlessly for testing or embedded into other apps.

Hajime Hoshi

💡 The cgo-free approach is made possible by purego, the Ebitengine team's library for calling C functions from Go without cgo.

Open Source Hits Frontier-Level Code Review at a Tenth of the Cost — PR-AF places #2 of 42 on Martian's Code-Review-Bench. Verified findings only, self-hosted, any open model.

AgentField.ai sponsor

📄 Four Ways to Do Super Fast Packet Processing in Go – AF_PACKET, AF_XDP, DPDK and Mellanox Direct Verbs compared, with real throughput numbers, and a library wrapping them. Andree Toonk

📄 Sloc Cloc and Code: Did I Just Get Buster Scrugged? – A tale of profiling scc after a Rust rival counted code 2.5x faster, and winning back the lead. Ben Boyter

📄 Implementing Type Contracts via Mutually Referencing Type Parameters Nick Tobey (DoltHub)

📄 I Contributed to Go: Here's How You Can Too Alex Pliutau

📄 The 14-Year Road to encoding/json/v2 Yoshi Yamaguchi

🛠 Code & Tools

gomodjail 2.0: An Experimental Jail for Go Modules — From the creator of Lima comes an interesting way to confine Go dependencies: mark a module with a comment in go.mod and a gomodjail analyze check fails if it can reach the filesystem, network, raw syscalls, etc.

Akihiro Suda

VHS 0.12: The 'Home Video Recorder' for Your CLI — A tool and scripting language for performing actions on the terminal that get recorded into an animated GIF, MP4, WebM, or PNG frames. Great for demos or tutorials. v0.12.0 lets you size the output by rows and columns (instead of just pixels).

Charm

🤖 yzma 1.26: Local LLM Inference from Go, Now in the Browser — Run vision and language models from Go through llama.cpp with no cgo required (thanks to purego and ffi). Notably, v1.26.0 adds WebAssembly support, so a TinyGo build can run inference directly on a web page.

The Hybrid Group

go-oracledb: An Official Pure Go Driver for Oracle Database — It's beta for now, but interesting to see an official Go client from Oracle. The established third party options are go-ora (also pure Go) and godror (which uses Oracle’s client libraries via cgo).

Oracle

📰 Classifieds

Your Go stack is minimal. Your data layer can be too. TimescaleDB extends Postgres for metrics and analytics. Get $1000 credit.

Software Engineer - Join our "kick ass" team! Our software team operates from 17 countries and we're looking for more exceptional engineers to join our team.

🔊 Oto 3.5 – Library to play audio on multiple platforms. Used by Ebitengine, it's now cgo-free on Linux and BSD using PulseAudio, with an ALSA fallback.
gofumpt 0.12 – Stricter formatter for Go that enforces additional rules beyond gofmt. Now based on Go 1.27's gofmt but works on Go 1.26 and up.
go-tui 0.20 – Build declarative terminal UIs with a React-inspired approach.
workers-go 0.35 – Run HTTP servers written in Go on Cloudflare Workers.
🌐 TZF 2.0 – Fast timezone finder from lat/long coordinates.
go-brrr 1.1 – Pure Go Brotli compression/decompression.